Improvement in door-springs



'Jg K. GILFILL-AN.

DOOR-SPRING. No.177,934. Patented May 30,1876.

NrFEfERsA FHcTmuTHcGRAPMER, WASHINGTON. D 2A UNITED STATES PATENT i QEEIcE.

i JAMESAK. GILFILLAN, OF SYRACUSE, NEW YORK, ASSIGNOR TO WILLIAM GILFILLAN, OF SAME PLAGE.

IMPRovEMENr IN DOOR-SPRINGS.

Specification forming part of Letters Patent No. 177,934, dated May 30, 1876; application led April 27, 1ere.

.To all whom it may concern Be it known that I, J AMES K. GILEILLAN, of the city of Syracuse and State of New York have invented new and useful linprovelnents in Door Springs; and I hereby declare that the following is a full, clear, and exact description of the same, reference being had to the accompanying drawings, forming a part hereof, in which- Figure l is a sectional View on the line in Fig. 2. Fig. 2 is anl edge View, the wood removed, on line w fw. Fig. 3 is a detail in section on the line y y. Fig. 4 is a detail in section on theline zz. Fig. 5 is a detail in section on the line a a. y

'Letters of reference indicate like parts in all the iigures of the drawing.

My invention consists ina pivoted slotted lever, a coiled spring of peculiar shape, a cylindrical centrally-pivoted fulcrum for said spring, and in lne-ans of adjusting the same, all being shown and described, and being iniproveinents on my Patent No. 17 4,516, March 7, 1876.

A is the supporting-plate, of usual construction, except in extending the bars or ribs a a and forming in theinner sides thereof grooves, in which the edges of the confiningplate b set and ride. B is a spring, coiled around the cylindrical fulcruiu G, its confined end passing beneath the confining-plate l), and its free end passing into and through the friction-roller D and washer d, which washer retains the said roller in the slotE of the pivoted bar F, to which isfattached the con necting-bar Gr, the said bar G being connected to the casing-hook H. The coniining-plate b has uponits side a lug, h, through which is a screw threaded aperture. ',Ihro'ugh the supporting-plate A passes the screw H', which enters and passes through the lug it, and by the turning of this screw; with any suitable tool, the confining-plate b is brought toward or moved from the supportingplate A, bringing with it the coniined end of the spring B, thus increasing or decreasing its strain upon the' pivoted lever F.

The operation of the device is as follows: The door being closed, the vfree end of the spring rests at apoint in the slot E farthest from the supporting-plate, and in this position exerts its greatest force upon the door.

As the door is changed from a closed to an open position, the free end of the pivoted bar F is drawn toward and partially through the large aperture I, Fig. 2, of the supporting- Vplate A, causing the free end of the spring B and its friction-roller D to traverse the slot E until the slot and spring are in -a line near and parallel to the supportingplate, and, while in this position, the door is open and the spring is exerting its least force upon it. By turning the screw H to the right, the confining-plate b is drawn near to the supporting-plate A, bringing with it the end of the spring, thus increasing its strain upon the slotted bar F and upon the door. By turning the said screw in the opposite direction the result is the reverse. The cylindri-` cal fulcrum is centrally pivoted, in order that it may partially rotate as the'spring operates.

I may construct the device without this adjusting-s'crew and confining-plate. In that case the end of the spring may be fastened firmly, in any 'suitable manner, tothe supporting-plate, or it may be continued one-half (additional) turn around the fulcruin and then extended upward and left, resting upon the rear surface of the supporting-plate A." But I prefer to use the device for connement and adjustment, as shown and described.

It is evident that the free end of the spring B will work in the slotted bar F without the friction-roller D, but I prefer to use said roller, as shown and described.

What I claim as new, and wish to secure by Letters Patent, isl 1. The combination of the slotted bar F,

coiled spring B, cylindrical fulcrum C. and plate A, substantially as shown and described. r 2. The combination of the slotted bar F, coiled spring B, friction-roller D, centrallypivoted cylindrical fulcrum C, and plate A, substantially as shown and described.

3. The combination of the coiled spring B,

cylindrical fulcrum C, and the confining-plate' b, adjustable toward and from the supportingplate A, as shown and'described.

JAMES K. GILFILLAN. Witnesses:

CHARLES R. BREED, ANDREW DRUMMA. 

